Technical Field
This disclosure relates to inhibitors of one or more proteins in the Wnt pathway, including inhibitors of one or more Wnt proteins, and compositions comprising the same. More particularly, it concerns the use of an indazole compound or salts or analogs thereof, in the treatment of disorders characterized by the activation of Wnt pathway signaling (e.g., cancer, abnormal cellular proliferation, angiogenesis, Alzheimer's disease, lung disease, fibrotic disorders, cartilage (chondral) defects, and osteoarthritis), the modulation of cellular events mediated by Wnt pathway signaling, as well as genetic diseases and neurological conditions/disorders/diseases due to mutations or dysregulation of the Wnt pathway and/or of one or more of Wnt signaling components. Also provided are methods for treating Wnt-related disease states.
Background
The Wnt growth factor family includes more than 10 genes identified in the mouse and at least 19 genes identified in the human. Members of the Wnt family of signaling molecules mediate many short- and long-range patterning processes during invertebrate and vertebrate development. The Wnt signaling pathway is known for its role in the inductive interactions that regulate growth and differentiation, and it also plays roles in the homeostatic maintenance of post-embryonic tissue integrity. Wnt stabilizes cytoplasmic β-catenin, which stimulates the expression of genes including c-myc, c-jun, fra-1, and cyclin D1. In addition, misregulation of Wnt signaling can cause developmental defects and is implicated in the genesis of several human cancers. The Wnt pathway has also been implicated in the maintenance of stem or progenitor cells in a growing list of adult tissues including skin, blood, gut, prostate, muscle, and the nervous system.
Dual specificity tyrosine-phosphorylation-regulated kinase 1A is an enzyme that in humans is encoded by the DYRK1A gene. DYRK1A is a member of the dual-specificity tyrosine phosphorylation-regulated kinase (DYRK) family. DYRK1A contains a nuclear targeting signal sequence, a protein kinase domain, a leucine zipper motif, and a highly conservative 13-consecutive-histidine repeat. It catalyzes its autophosphorylation on serine/threonine and tyrosine residues. It may play a significant role in a signaling pathway regulating cell proliferation and may be involved in brain development. DYRK1A is localized in the Down syndrome critical region of chromosome 21, and is considered to be a candidate gene for learning defects associated with Down syndrome. DYRK1A is also expressed in adult brain neurons, indicating that DYRK1A may play a role in the mature central nervous system. Thus, several lines of evidence point to some synaptic functions of DYRK1A. For instance, it has been found that DYRK1A phosphorylates and modulates the interaction of several components of the endocytic protein complex machinery (Dynamin 1, Amphiphysin, and Synaptojanin), suggesting a role in synaptic vesicle recycling. In addition, a polymorphism (SNP) in DYRK1A was found to be associated with HIV-1 replication in monocyte-derived macrophages, as well as with progression to AIDS in two independent cohorts of HIV-1-infected individuals.